A new report is casting doubt on the value of dietary supplements.

Consumer Reports put out a list of 15 ingredients in supplements that they say could be potentially harmful.

Some of the side effects are minor, like dizziness and vomiting.

Doctors say more serious and even fatal problems are possible, like coma and cancer, depending on pre-existing medical conditions and the quantity of the ingredient taken.

Health experts say many ingredients on the list may also interact with other prescription or some common over-the-counter drugs like aspirin.

"Even though it may seem like a benign supplement, it's really always best to talk to your physician or your pharmacist before taking any of these things," says Dr. Nancy Lavine, an internist at Northwell Health.

A full list of the ingredients and the risks associated with them is located on the Consumer Reports website.